Fragmentation currently uses an allocated array to store the
fragment skbs, and then keeps track of which have been sent
and which are still pending etc. This is rather complicated;
make it simpler by just chaining the fragments into skb->next
and removing from that list when sent. Also simplifies all
code that needs to touch fragments, since it now only needs
to walk the skb->next list.
This is a prerequisite for fixing the stored packet code,
which I need to do for proper aggregation packet storing.
Signed-off-by: Johannes Berg <johannes@xxxxxxxxxxxxxxxx>
---
net/mac80211/ieee80211_i.h | 7
net/mac80211/tx.c | 328 +++++++++++++++++++++------------------------
net/mac80211/util.c | 17 --
net/mac80211/wep.c | 21 --
net/mac80211/wpa.c | 28 +--
5 files changed, 175 insertions(+), 226 deletions(-)
--- wireless-testing.orig/net/mac80211/ieee80211_i.h 2009-03-21 17:06:34.000000000 +0100
+++ wireless-testing/net/mac80211/ieee80211_i.h 2009-03-21 17:08:48.000000000 +0100
@@ -149,11 +149,6 @@ struct ieee80211_tx_data {
struct ieee80211_channel *channel;
- /* Extra fragments (in addition to the first fragment
- * in skb) */
- struct sk_buff **extra_frag;
- int num_extra_frag;
-
u16 ethertype;
unsigned int flags;
};
@@ -191,8 +186,6 @@ struct ieee80211_rx_data {
struct ieee80211_tx_stored_packet {
struct sk_buff *skb;
- struct sk_buff **extra_frag;
- int num_extra_frag;
};
struct beacon_data {
--- wireless-testing.orig/net/mac80211/tx.c 2009-03-21 17:06:18.000000000 +0100
+++ wireless-testing/net/mac80211/tx.c 2009-03-21 17:08:48.000000000 +0100
@@ -34,8 +34,7 @@
#define IEEE80211_TX_OK 0
#define IEEE80211_TX_AGAIN 1
-#define IEEE80211_TX_FRAG_AGAIN 2
-#define IEEE80211_TX_PENDING 3
+#define IEEE80211_TX_PENDING 2
/* misc utils */
@@ -702,17 +701,62 @@ ieee80211_tx_h_sequence(struct ieee80211
return TX_CONTINUE;
}
+static int ieee80211_fragment(struct ieee80211_local *local,
+ struct sk_buff *skb, int hdrlen,
+ int frag_threshold)
+{
+ struct sk_buff *tail = skb, *tmp;
+ int per_fragm = frag_threshold - hdrlen - FCS_LEN;
+ int pos = hdrlen + per_fragm;
+ int rem = skb->len - hdrlen - per_fragm;
+
+ if (WARN_ON(rem < 0))
+ return -EINVAL;
+
+ while (rem) {
+ int fraglen = per_fragm;
+
+ if (fraglen > rem)
+ fraglen = rem;
+ rem -= fraglen;
+ tmp = dev_alloc_skb(local->tx_headroom +
+ frag_threshold +
+ IEEE80211_ENCRYPT_HEADROOM +
+ IEEE80211_ENCRYPT_TAILROOM);
+ if (!tmp)
+ return -ENOMEM;
+ tail->next = tmp;
+ tail = tmp;
+ skb_reserve(tmp, local->tx_headroom +
+ IEEE80211_ENCRYPT_HEADROOM);
+ /* copy control information */
+ memcpy(tmp->cb, skb->cb, sizeof(tmp->cb));
+ skb_copy_queue_mapping(tmp, skb);
+ tmp->priority = skb->priority;
+ tmp->do_not_encrypt = skb->do_not_encrypt;
+ tmp->dev = skb->dev;
+ tmp->iif = skb->iif;
+
+ /* copy header and data */
+ memcpy(skb_put(tmp, hdrlen), skb->data, hdrlen);
+ memcpy(skb_put(tmp, fraglen), skb->data + pos, fraglen);
+
+ pos += fraglen;
+ }
+
+ skb->len = hdrlen + per_fragm;
+ return 0;
+}
+
static ieee80211_tx_result debug_noinline
ieee80211_tx_h_fragment(struct ieee80211_tx_data *tx)
{
- struct ieee80211_tx_info *info = IEEE80211_SKB_CB(tx->skb);
- struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)tx->skb->data;
- size_t hdrlen, per_fragm, num_fragm, payload_len, left;
- struct sk_buff **frags, *first, *frag;
- int i;
- u16 seq;
- u8 *pos;
+ struct sk_buff *skb = tx->skb;
+ struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
+ struct ieee80211_hdr *hdr = (void *)skb->data;
int frag_threshold = tx->local->fragmentation_threshold;
+ int hdrlen;
+ int fragnum;
if (!(tx->flags & IEEE80211_TX_FRAGMENTED))
return TX_CONTINUE;
@@ -725,58 +769,35 @@ ieee80211_tx_h_fragment(struct ieee80211
if (WARN_ON(info->flags & IEEE80211_TX_CTL_AMPDU))
return TX_DROP;
- first = tx->skb;
-
hdrlen = ieee80211_hdrlen(hdr->frame_control);
- payload_len = first->len - hdrlen;
- per_fragm = frag_threshold - hdrlen - FCS_LEN;
- num_fragm = DIV_ROUND_UP(payload_len, per_fragm);
-
- frags = kzalloc(num_fragm * sizeof(struct sk_buff *), GFP_ATOMIC);
- if (!frags)
- goto fail;
- hdr->frame_control |= cpu_to_le16(IEEE80211_FCTL_MOREFRAGS);
- seq = le16_to_cpu(hdr->seq_ctrl) & IEEE80211_SCTL_SEQ;
- pos = first->data + hdrlen + per_fragm;
- left = payload_len - per_fragm;
- for (i = 0; i < num_fragm - 1; i++) {
- struct ieee80211_hdr *fhdr;
- size_t copylen;
-
- if (left <= 0)
- goto fail;
+ /* internal error, why is TX_FRAGMENTED set? */
+ if (WARN_ON(skb->len <= frag_threshold))
+ return TX_DROP;
- /* reserve enough extra head and tail room for possible
- * encryption */
- frag = frags[i] =
- dev_alloc_skb(tx->local->tx_headroom +
- frag_threshold +
- IEEE80211_ENCRYPT_HEADROOM +
- IEEE80211_ENCRYPT_TAILROOM);
- if (!frag)
- goto fail;
+ /*
+ * Now fragment the frame. This will allocate all the fragments and
+ * chain them (using skb as the first fragment) to skb->next.
+ * During transmission, we will remove the successfully transmitted
+ * fragments from this list. When the low-level driver rejects one
+ * of the fragments then we will simply pretend to accept the skb
+ * but store it away as pending.
+ */
+ if (ieee80211_fragment(tx->local, skb, hdrlen, frag_threshold))
+ return TX_DROP;
- /* Make sure that all fragments use the same priority so
- * that they end up using the same TX queue */
- frag->priority = first->priority;
-
- skb_reserve(frag, tx->local->tx_headroom +
- IEEE80211_ENCRYPT_HEADROOM);
-
- /* copy TX information */
- info = IEEE80211_SKB_CB(frag);
- memcpy(info, first->cb, sizeof(frag->cb));
-
- /* copy/fill in 802.11 header */
- fhdr = (struct ieee80211_hdr *) skb_put(frag, hdrlen);
- memcpy(fhdr, first->data, hdrlen);
- fhdr->seq_ctrl = cpu_to_le16(seq | ((i + 1) & IEEE80211_SCTL_FRAG));
-
- if (i == num_fragm - 2) {
- /* clear MOREFRAGS bit for the last fragment */
- fhdr->frame_control &= cpu_to_le16(~IEEE80211_FCTL_MOREFRAGS);
- } else {
+ /* update duration/seq/flags of fragments */
+ fragnum = 0;
+ do {
+ int next_len;
+ const __le16 morefrags = cpu_to_le16(IEEE80211_FCTL_MOREFRAGS);
+
+ hdr = (void *)skb->data;
+ info = IEEE80211_SKB_CB(skb);
+
+ if (skb->next) {
+ hdr->frame_control |= morefrags;
+ next_len = skb->next->len;
/*
* No multi-rate retries for fragmented frames, that
* would completely throw off the NAV at other STAs.
@@ -787,37 +808,16 @@ ieee80211_tx_h_fragment(struct ieee80211
info->control.rates[4].idx = -1;
BUILD_BUG_ON(IEEE80211_TX_MAX_RATES != 5);
info->flags &= ~IEEE80211_TX_CTL_RATE_CTRL_PROBE;
+ } else {
+ hdr->frame_control &= ~morefrags;
+ next_len = 0;
}
-
- /* copy data */
- copylen = left > per_fragm ? per_fragm : left;
- memcpy(skb_put(frag, copylen), pos, copylen);
-
- skb_copy_queue_mapping(frag, first);
-
- frag->do_not_encrypt = first->do_not_encrypt;
- frag->dev = first->dev;
- frag->iif = first->iif;
-
- pos += copylen;
- left -= copylen;
- }
- skb_trim(first, hdrlen + per_fragm);
-
- tx->num_extra_frag = num_fragm - 1;
- tx->extra_frag = frags;
+ hdr->duration_id = ieee80211_duration(tx, 0, next_len);
+ hdr->seq_ctrl |= cpu_to_le16(fragnum & IEEE80211_SCTL_FRAG);
+ fragnum++;
+ } while ((skb = skb->next));
return TX_CONTINUE;
-
- fail:
- if (frags) {
- for (i = 0; i < num_fragm - 1; i++)
- if (frags[i])
- dev_kfree_skb(frags[i]);
- kfree(frags);
- }
- I802_DEBUG_INC(tx->local->tx_handlers_drop_fragment);
- return TX_DROP;
}
static ieee80211_tx_result debug_noinline
@@ -845,27 +845,19 @@ ieee80211_tx_h_encrypt(struct ieee80211_
static ieee80211_tx_result debug_noinline
ieee80211_tx_h_calculate_duration(struct ieee80211_tx_data *tx)
{
- struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)tx->skb->data;
- int next_len, i;
- int group_addr = is_multicast_ether_addr(hdr->addr1);
-
- if (!(tx->flags & IEEE80211_TX_FRAGMENTED)) {
- hdr->duration_id = ieee80211_duration(tx, group_addr, 0);
- return TX_CONTINUE;
- }
-
- hdr->duration_id = ieee80211_duration(tx, group_addr,
- tx->extra_frag[0]->len);
-
- for (i = 0; i < tx->num_extra_frag; i++) {
- if (i + 1 < tx->num_extra_frag)
- next_len = tx->extra_frag[i + 1]->len;
- else
- next_len = 0;
+ struct sk_buff *skb = tx->skb;
+ struct ieee80211_hdr *hdr;
+ int next_len;
+ bool group_addr;
- hdr = (struct ieee80211_hdr *)tx->extra_frag[i]->data;
- hdr->duration_id = ieee80211_duration(tx, 0, next_len);
- }
+ do {
+ hdr = (void *) skb->data;
+ next_len = skb->next ? skb->next->len : 0;
+ group_addr = is_multicast_ether_addr(hdr->addr1);
+
+ hdr->duration_id =
+ ieee80211_duration(tx, group_addr, next_len);
+ } while ((skb = skb->next));
return TX_CONTINUE;
}
@@ -873,19 +865,16 @@ ieee80211_tx_h_calculate_duration(struct
static ieee80211_tx_result debug_noinline
ieee80211_tx_h_stats(struct ieee80211_tx_data *tx)
{
- int i;
+ struct sk_buff *skb = tx->skb;
if (!tx->sta)
return TX_CONTINUE;
tx->sta->tx_packets++;
- tx->sta->tx_fragments++;
- tx->sta->tx_bytes += tx->skb->len;
- if (tx->extra_frag) {
- tx->sta->tx_fragments += tx->num_extra_frag;
- for (i = 0; i < tx->num_extra_frag; i++)
- tx->sta->tx_bytes += tx->extra_frag[i]->len;
- }
+ do {
+ tx->sta->tx_fragments++;
+ tx->sta->tx_bytes += skb->len;
+ } while ((skb = skb->next));
return TX_CONTINUE;
}
@@ -1099,45 +1088,36 @@ static int ieee80211_tx_prepare(struct i
return 0;
}
-static int __ieee80211_tx(struct ieee80211_local *local, struct sk_buff *skb,
+static int __ieee80211_tx(struct ieee80211_local *local,
struct ieee80211_tx_data *tx)
{
+ struct sk_buff *skb = tx->skb, *next;
struct ieee80211_tx_info *info;
- int ret, i;
+ int ret;
+ bool fragm = false;
- if (skb) {
+ local->mdev->trans_start = jiffies;
+
+ while (skb) {
if (ieee80211_queue_stopped(&local->hw,
skb_get_queue_mapping(skb)))
return IEEE80211_TX_PENDING;
- ret = local->ops->tx(local_to_hw(local), skb);
- if (ret)
- return IEEE80211_TX_AGAIN;
- local->mdev->trans_start = jiffies;
- ieee80211_led_tx(local, 1);
- }
- if (tx->extra_frag) {
- for (i = 0; i < tx->num_extra_frag; i++) {
- if (!tx->extra_frag[i])
- continue;
- info = IEEE80211_SKB_CB(tx->extra_frag[i]);
+ if (fragm) {
+ info = IEEE80211_SKB_CB(skb);
info->flags &= ~(IEEE80211_TX_CTL_CLEAR_PS_FILT |
IEEE80211_TX_CTL_FIRST_FRAGMENT);
- if (ieee80211_queue_stopped(&local->hw,
- skb_get_queue_mapping(tx->extra_frag[i])))
- return IEEE80211_TX_FRAG_AGAIN;
-
- ret = local->ops->tx(local_to_hw(local),
- tx->extra_frag[i]);
- if (ret)
- return IEEE80211_TX_FRAG_AGAIN;
- local->mdev->trans_start = jiffies;
- ieee80211_led_tx(local, 1);
- tx->extra_frag[i] = NULL;
}
- kfree(tx->extra_frag);
- tx->extra_frag = NULL;
+
+ next = skb->next;
+ ret = local->ops->tx(local_to_hw(local), skb);
+ if (ret != NETDEV_TX_OK)
+ return IEEE80211_TX_AGAIN;
+ tx->skb = skb = next;
+ ieee80211_led_tx(local, 1);
+ fragm = true;
}
+
return IEEE80211_TX_OK;
}
@@ -1149,7 +1129,6 @@ static int invoke_tx_handlers(struct iee
{
struct sk_buff *skb = tx->skb;
ieee80211_tx_result res = TX_DROP;
- int i;
#define CALL_TXH(txh) \
res = txh(tx); \
@@ -1173,11 +1152,13 @@ static int invoke_tx_handlers(struct iee
txh_done:
if (unlikely(res == TX_DROP)) {
I802_DEBUG_INC(tx->local->tx_handlers_drop);
- dev_kfree_skb(skb);
- for (i = 0; i < tx->num_extra_frag; i++)
- if (tx->extra_frag[i])
- dev_kfree_skb(tx->extra_frag[i]);
- kfree(tx->extra_frag);
+ while (skb) {
+ struct sk_buff *next;
+
+ next = skb->next;
+ dev_kfree_skb(skb);
+ skb = next;
+ }
return -1;
} else if (unlikely(res == TX_QUEUED)) {
I802_DEBUG_INC(tx->local->tx_handlers_queued);
@@ -1194,7 +1175,7 @@ static int ieee80211_tx(struct net_devic
struct ieee80211_tx_data tx;
ieee80211_tx_result res_prepare;
struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
- int ret, i;
+ int ret;
u16 queue;
queue = skb_get_queue_mapping(skb);
@@ -1225,7 +1206,7 @@ static int ieee80211_tx(struct net_devic
goto out;
retry:
- ret = __ieee80211_tx(local, skb, &tx);
+ ret = __ieee80211_tx(local, &tx);
if (ret) {
struct ieee80211_tx_stored_packet *store;
@@ -1240,9 +1221,6 @@ retry:
store = &local->pending_packet[queue];
- if (ret == IEEE80211_TX_FRAG_AGAIN)
- skb = NULL;
-
set_bit(queue, local->queues_pending);
smp_mb();
/*
@@ -1260,22 +1238,23 @@ retry:
clear_bit(queue, local->queues_pending);
goto retry;
}
- store->skb = skb;
- store->extra_frag = tx.extra_frag;
- store->num_extra_frag = tx.num_extra_frag;
+ store->skb = tx.skb;
}
out:
rcu_read_unlock();
return 0;
drop:
- if (skb)
- dev_kfree_skb(skb);
- for (i = 0; i < tx.num_extra_frag; i++)
- if (tx.extra_frag[i])
- dev_kfree_skb(tx.extra_frag[i]);
- kfree(tx.extra_frag);
rcu_read_unlock();
+
+ skb = tx.skb;
+ while (skb) {
+ struct sk_buff *next;
+
+ next = skb->next;
+ dev_kfree_skb(skb);
+ skb = next;
+ }
return 0;
}
@@ -1810,17 +1789,21 @@ int ieee80211_subif_start_xmit(struct sk
*/
void ieee80211_clear_tx_pending(struct ieee80211_local *local)
{
- int i, j;
- struct ieee80211_tx_stored_packet *store;
+ struct sk_buff *skb;
+ int i;
for (i = 0; i < local->hw.queues; i++) {
if (!test_bit(i, local->queues_pending))
continue;
- store = &local->pending_packet[i];
- kfree_skb(store->skb);
- for (j = 0; j < store->num_extra_frag; j++)
- kfree_skb(store->extra_frag[j]);
- kfree(store->extra_frag);
+
+ skb = local->pending_packet[i].skb;
+ while (skb) {
+ struct sk_buff *next;
+
+ next = skb->next;
+ dev_kfree_skb(skb);
+ skb = next;
+ }
clear_bit(i, local->queues_pending);
}
}
@@ -1854,14 +1837,11 @@ void ieee80211_tx_pending(unsigned long
netif_start_subqueue(local->mdev, i);
store = &local->pending_packet[i];
- tx.extra_frag = store->extra_frag;
- tx.num_extra_frag = store->num_extra_frag;
tx.flags = 0;
- ret = __ieee80211_tx(local, store->skb, &tx);
- if (ret) {
- if (ret == IEEE80211_TX_FRAG_AGAIN)
- store->skb = NULL;
- } else {
+ tx.skb = store->skb;
+ ret = __ieee80211_tx(local, &tx);
+ store->skb = tx.skb;
+ if (!ret) {
clear_bit(i, local->queues_pending);
ieee80211_wake_queue(&local->hw, i);
}
--- wireless-testing.orig/net/mac80211/wep.c 2009-03-21 17:06:18.000000000 +0100
+++ wireless-testing/net/mac80211/wep.c 2009-03-21 17:08:48.000000000 +0100
@@ -329,24 +329,17 @@ static int wep_encrypt_skb(struct ieee80
ieee80211_tx_result
ieee80211_crypto_wep_encrypt(struct ieee80211_tx_data *tx)
{
- int i;
+ struct sk_buff *skb;
ieee80211_tx_set_protected(tx);
- if (wep_encrypt_skb(tx, tx->skb) < 0) {
- I802_DEBUG_INC(tx->local->tx_handlers_drop_wep);
- return TX_DROP;
- }
-
- if (tx->extra_frag) {
- for (i = 0; i < tx->num_extra_frag; i++) {
- if (wep_encrypt_skb(tx, tx->extra_frag[i])) {
- I802_DEBUG_INC(tx->local->
- tx_handlers_drop_wep);
- return TX_DROP;
- }
+ skb = tx->skb;
+ do {
+ if (wep_encrypt_skb(tx, skb) < 0) {
+ I802_DEBUG_INC(tx->local->tx_handlers_drop_wep);
+ return TX_DROP;
}
- }
+ } while ((skb = skb->next));
return TX_CONTINUE;
}
--- wireless-testing.orig/net/mac80211/wpa.c 2009-03-21 17:06:18.000000000 +0100
+++ wireless-testing/net/mac80211/wpa.c 2009-03-21 17:08:48.000000000 +0100
@@ -196,19 +196,13 @@ ieee80211_tx_result
ieee80211_crypto_tkip_encrypt(struct ieee80211_tx_data *tx)
{
struct sk_buff *skb = tx->skb;
- int i;
ieee80211_tx_set_protected(tx);
- if (tkip_encrypt_skb(tx, skb) < 0)
- return TX_DROP;
-
- if (tx->extra_frag) {
- for (i = 0; i < tx->num_extra_frag; i++) {
- if (tkip_encrypt_skb(tx, tx->extra_frag[i]))
- return TX_DROP;
- }
- }
+ do {
+ if (tkip_encrypt_skb(tx, skb) < 0)
+ return TX_DROP;
+ } while ((skb = skb->next));
return TX_CONTINUE;
}
@@ -428,19 +422,13 @@ ieee80211_tx_result
ieee80211_crypto_ccmp_encrypt(struct ieee80211_tx_data *tx)
{
struct sk_buff *skb = tx->skb;
- int i;
ieee80211_tx_set_protected(tx);
- if (ccmp_encrypt_skb(tx, skb) < 0)
- return TX_DROP;
-
- if (tx->extra_frag) {
- for (i = 0; i < tx->num_extra_frag; i++) {
- if (ccmp_encrypt_skb(tx, tx->extra_frag[i]))
- return TX_DROP;
- }
- }
+ do {
+ if (ccmp_encrypt_skb(tx, skb) < 0)
+ return TX_DROP;
+ } while ((skb = skb->next));
return TX_CONTINUE;
}
--- wireless-testing.orig/net/mac80211/util.c 2009-03-21 17:06:18.000000000 +0100
+++ wireless-testing/net/mac80211/util.c 2009-03-21 17:08:48.000000000 +0100
@@ -166,18 +166,13 @@ int ieee80211_get_mesh_hdrlen(struct iee
void ieee80211_tx_set_protected(struct ieee80211_tx_data *tx)
{
- struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) tx->skb->data;
+ struct sk_buff *skb = tx->skb;
+ struct ieee80211_hdr *hdr;
- hdr->frame_control |= cpu_to_le16(IEEE80211_FCTL_PROTECTED);
- if (tx->extra_frag) {
- struct ieee80211_hdr *fhdr;
- int i;
- for (i = 0; i < tx->num_extra_frag; i++) {
- fhdr = (struct ieee80211_hdr *)
- tx->extra_frag[i]->data;
- fhdr->frame_control |= cpu_to_le16(IEEE80211_FCTL_PROTECTED);
- }
- }
+ do {
+ hdr = (struct ieee80211_hdr *) skb->data;
+ hdr->frame_control |= cpu_to_le16(IEEE80211_FCTL_PROTECTED);
+ } while ((skb = skb->next));
}
int ieee80211_frame_duration(struct ieee80211_local *local, size_t len,
--
--
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